iac
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
On an '85, the IAC is located on the bottom of the throttle body. It's screwed in from the passenger side. Once that is removed you can clean the pintel with throttle body cleaner, and the hole where it was screwed into with the same.
Overtime the pintel and the opening get carboned up bad enough to affect its' operation.
Overtime the pintel and the opening get carboned up bad enough to affect its' operation.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
To service the IAC you should extend it's pintel; afterwards you will need to set base idle and maybe the TPS.
My method is explained on my site.
If the IAC gasket does not come off in tact you can cut one from a sheet of gasket material of proper thickness.
I spary the IAC pintel with carb cleaner and use a cottom swab soaked in carb cleaner to clean the bore. Then I use a mirror and light to assure there are no cotton fibers stuck inside the bore.
My method is explained on my site.
If the IAC gasket does not come off in tact you can cut one from a sheet of gasket material of proper thickness.
I spary the IAC pintel with carb cleaner and use a cottom swab soaked in carb cleaner to clean the bore. Then I use a mirror and light to assure there are no cotton fibers stuck inside the bore.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
These guys have you in the right direction.
I recommend taking the throttle body off the plenum. The IAC can be removed much easier and you can clean the throttle body and IAC completely. I have not been able to find just the IAC gasket itself anywhere. You can make a new one from gasket paper (autozone) or buy a new IAC with the gasket.
Once the IAC is out. I used throttle body cleaner and a tooth brush on the windings and IAC air passage. Clean the throttle body good. When you're ready to install the IAC. Make sure the tip of the pintle is no further than 1 1/8" from the flange. If any further the motor windings may be damaged. Becareful in this area because the TPS can be moved and throw the voltage reading off.
The IAC is a steper motor that is controled by the ECM only. At idle the IAC pintle is moved in or out of the air passage accordingly. Once the throttle plates are opened the IAC has no effect.
If you would like to also set the minimal idle while your there...let us know.
I recommend taking the throttle body off the plenum. The IAC can be removed much easier and you can clean the throttle body and IAC completely. I have not been able to find just the IAC gasket itself anywhere. You can make a new one from gasket paper (autozone) or buy a new IAC with the gasket.
Once the IAC is out. I used throttle body cleaner and a tooth brush on the windings and IAC air passage. Clean the throttle body good. When you're ready to install the IAC. Make sure the tip of the pintle is no further than 1 1/8" from the flange. If any further the motor windings may be damaged. Becareful in this area because the TPS can be moved and throw the voltage reading off.
The IAC is a steper motor that is controled by the ECM only. At idle the IAC pintle is moved in or out of the air passage accordingly. Once the throttle plates are opened the IAC has no effect.
If you would like to also set the minimal idle while your there...let us know.
